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Glacier stability depends on the interaction between ice temperature and ablation, processes mediated by firn cover. Although firn-covered glaciers have been extensively investigated, firn-free glacier dynamics remain less clear. This study analyzes the coupled response of ice temperature and ablation to air temperature on the firn-free Aug 1st glacier in the northeastern Tibetan plateau. Results indicate that surface ice temperature is positively correlated with air temperature; however, without firn to store meltwater, latent heat uptake and runoff-related heat loss reduce the rate of surface warming. Increased ablation also limits heat penetration, encouraging active-layer thinning under stable internal ice temperatures. By contrast, ice temperature has little effect on ablation, which is governed mainly by air temperature. These results advance knowledge of glacier thermal behavior and underscore the importance of glacier type in modeling ice temperature evolution.

Ewing sarcoma is a rare and aggressive cancer of the bone and soft tissues primarily affecting children and young adults. Prognosis for patients with metastatic or recurrent disease remains poor despite intensive multimodal therapy, highlighting the need of novel therapeutic approaches. The disialoganglioside GD2 is highly expressed on Ewing sarcoma cells, making this tumor eligible for anti-GD2 immunotherapy with dinutuximab beta. Through in vitro and in vivo approaches, this study demonstrated that dinutuximab beta effectively suppressed tumor growth by 60% (p = 0.0135) and improved survival rate by 68% (p = 0.0006) in a mouse model xenograft. The combination therapy with doxorubicin demonstrated superior efficacy compared to monotherapy, with enhanced tumor suppression (86%; p = 0.0009) and an extension of survival rate (146%; p = 0.000025). This study showed that dinutuximab beta, particularly in combination with standard chemotherapy, offers a promising approach to improve outcomes for high-risk Ewing sarcoma patients, providing a more effective alternative to current treatments.

Conventional methods for preparing nucleosomes are time-consuming and technically demanding. In the present study, we extended the approach of generating nucleosomes in Escherichia coli by the co-expression of all four histones, allowing nucleosomes to be assembled in cells. The bacterially reconstituted nucleosomes can be readily prepared from the E. coli cells and directly subjected to cryo-EM single particle analysis. Using this method, we obtained a 2.56 Å nucleosome structure that is highly similar to a previously reported nucleosome crystal structure, validating the use of nucleosomes formed in E. coli for cryo-EM analysis. Unexpectedly, we also discovered a non-canonical nucleosome structure, in which two hexasomes are closely packed. This system provides a robust and efficient platform for structural studies of nucleosomes and nucleosome variants, and may facilitate the discovery of chromatin architectures.

In axons, α/β-spectrins, adducin, and actin filaments assemble into a lattice underneath the plasma membrane, but the mechanistic events leading to this membrane-associated periodic skeleton (MPS) are unclear. Visualizing MPS-components in developing axons, we found distal focal patches containing spectrins and adducin (but sparse actin filaments) with biophysical properties reminiscent of biomolecular condensation. Overexpressing spectrin repeats - constituents of α/β-spectrins - in heterologous cells triggered condensate formation, and preventing the association of βII-spectrin with actin filaments or membranes also facilitated condensation. Introducing a stretch of spectrin-repeats in neurons before MPS establishment triggered ectopic condensate-like structures in the soma and disrupted the axonal lattice, advocating a functional role for biomolecular condensation. We propose a condensation-assembly model where spectrin-repeats trigger focal phase separated condensates, providing a nidus for MPS assembly that recruits actin filaments to ultimately generate the stable lattice. Our overall model is supported by recent studies showing phase-separation via coiled-coil domains and recruitment/polymerization of actin by other condensate-forming proteins.

GLUT1 facilitates a continuous flow of glucose across the inner and outer blood-retinal barriers (BRBs) to support vision. To understand the extent to which photoreceptors rely on glucose transport across the outer BRB, we generated a tamoxifen-inducible conditional knockout of Slc2a1 in the retinal pigment epithelium (RPE) (RPE-iΔGlut1). In the RPE-iΔGlut1 mice, rod photoreceptors exhibited impaired outer segment renewal and decreased the expression of proteins involved in phototransduction and ciliary transport. Proteins regulating the retinal stress response increased. Cone photoreceptors were functional and viable 15 months post-tamoxifen treatment in the RPE-iΔGlut1 mice, while 70% of the rods died. When Slc2a1 was genetically deleted from rods (Rod-iΔGlut1 mice), rod degeneration was faster than in the RPE-iΔGlut1 mice. These findings suggest that rods are more dependent on glucose than cones, and that glucose from the deep vascular plexus may support cone function and viability and slow the rate of rod death.

This article explored the differences in pyroptosis mediated by calcium oxalate monohydrate (COM) crystals with sizes of 100 nm, 1 μm, 3 μm, 5 μm, and 10 μm and were used to induce pyroptosis of HK-2 cells. The proportion of pyroptosis cells was detected by caspase-1/PI double staining. Three small-sized COM crystals (0.1-3 μm) could be endocytosis by HK-2 cells and increased intracellular oxidative stress, which further promoted the activation of NLRP3 inflammasome and pyroptosis. The two COM crystals with large sizes (3-10 μm) were difficult to endocytose, and the main mechanism was the crystal adhesion, leading to pyroptosis. Crystal endocytosis leads to higher pyroptosis. The pyroptosis rates mediated by COM with different sizes were as follows: COM-100nm (17.81%) > COM-1μm (17.28%) > COM-3μm (17.25%) > COM-5μm (12.44%) > COM-10μm (9.05%). The smaller the COM crystal size, the higher the pyroptosis rate, which is related to the stronger oxidative stress.

Dysphagia in older adults causes serious complications, and efficient and scalable screenings are needed. This prospective multicenter study developed interpretable machine learning (ML) models for the early identification and staging of dysphagia. Nine ML models were built using the clinical data from 1,235 patients and externally validated on 720 patients. All patients were older adults from seven Suzhou hospitals whose dysphagia was confirmed via videofluoroscopic swallowing studies. Features were selected via random forest, and model interpretability was analyzed with SHapley Additive exPlanations (SHAP). The CatBoost model achieved an area under the receiver operating characteristic curve (AUC) of 0.914 for binary classification, while neural network gave AUC 0.884 for multiclass classification. External validation confirmed robustness (binary AUC, 0.909 and multiclass macro-AUC, 0.860). SHAP identified ten core features-oral/pharyngeal function influenced all stages, and masticatory/phonatory features acted selectively. A web application was created accordingly to facilitate real-time screening and stratify dysphagia patients.

Second harmonic generation (SHG) is a nonlinear phenomenon in which incident electromagnetic wave signals are converted into harmonic signals with doubled frequency. In this paper, a method has been proposed to enhance the SHG using metafilm, enabling the measurement of refractive index and incident angle. Metafilm refers to artificially constructed layered structures. Nonlinear frequency conversion within metafilms yields dual-mode harmonics, which can effectively distinguish the refractive index of sample layers. When the sample layer is composed of biomedical materials, the fundamental mode can distinguish enamel from dentin, while the second harmonic mode can effectively distinguish normal cells from cancerous cells. Finally, we consider the influences of thickness errors and material losses on detection performance and find that the system has good stability. This non-contact measurement method with extended range shows broad application prospects in the fields of biological tissue composition analysis and medical diagnosis.

Neuroinflammation is a major driver of neurodegenerative and psychiatric disease, yet current therapies have limited brain penetration and efficacy. We investigated microtesla magnetic therapy (MMT), a brief transcranial exposure to time-varied electromagnetic fields (TV-EMFs), as a noninvasive approach to modulate neuroimmune inflammation. In human peripheral blood mononuclear cells, MMT suppressed lipopolysaccharide (LPS)-induced TNFα and IL-1β release and reduced NF-κB activation in monocyte and macrophage lines. In rats with intracerebral LPS injection, a model of progressive neuroinflammation, repeated head-localized MMT markedly decreased microgliosis, astrogliosis, and lesion size. In a neuron-immune cell model, MMT reduced cytokine-driven and paraquat-induced oxidative stress, producing both indirect and direct neuroprotection lasting up to 48 h. Collectively, these findings validate transcranial MMT as a promising, noninvasive biophysical therapy for neuroinflammatory conditions. Both acute and repetitive TV-EMF protocols delivered robust anti-inflammatory, antioxidant, and neuroprotective effects, demonstrating the therapeutic potential of precisely modulated EMFs to safely manage neuroinflammation.